Defender for Endpoint and Antivirus
CVE-2026-45584: Microsoft Defender Remote Code Execution Vulnerability
Heap-based buffer overflow in Microsoft Defender allows an unauthorized attacker to execute code over a network.
Published
ExploitedNot in CISA KEV
Ransomware useNot reportedPer CISA
SeverityHIGHCVSS 3.1 8.1
EPSS0.71%Chance of exploitation in 30 days
Public exploitNot tracked
FixAvailable
Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.
Affected and fixed versions
| Product / branch | Fixed in |
|---|---|
| Microsoft Malware Protection Engine 1.1 | 1.1.26040.8 or later |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
Heap-based buffer overflow in Microsoft Defender allows an unauthorized attacker to execute code over a network.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 11 Oct 2026.